The Castle of Fyrien (S03E07)

Gwen is thrown into a heart-wrenching situation when she must decide between saving her estranged brother, Elyan, and Arthur, the prince of Camelot and her true love. With Cenred poised to take one of their lives, Gwen is faced with an agonizing choice. As loyalty, love, and friendship are pushed to their limits, Arthur, Merlin, and Gwen join forces to devise a plan to escape this grim predicament. Meanwhile, Morgana and Morgause are determined to thwart their efforts. Will good triumph over evil, or will Gwen face the painful loss of another loved one?